Moisture Requirements for Gelatinisation of Rice

The extent of gelatinisation achieved by heating rice at various moisture contents was determined by an X‐Ray diffraction technique and a method involving the differential alkali solubility of amylose in raw and gelatinised starch. The results obtained by these methods agreed closely (γ = 0.980) confirming that the alkali solubilisation technique gave a measure of starch crystallinity. Above 20% moisture content the extent of gelatinization was governed by the amount of water present. Gelatinisation was not completed unless the moisture content exceeded 40%, which corresponds to the typical moisture level of rice which has been soaked and steamed as in the parboiling process.